CAJ | 학술논문

±1000 kV直流在中国是一个新的电压等级,为保证设计的经济性和可靠性,需对不同海拔地区空气间隙距离的选择进行试验研究。在北京的特高压直流试验基地和海拔4 300 m的西藏高海拔试验基地采用相同结构的±1 000 kV真型尺寸模拟塔头空气间隙进行了冲击放电试验,获得了相应的操作冲击和雷电冲击放电特性曲线。通过对西藏基地得到的操作冲击放电电压采用GB/T 16927.1—1997、IEC 60071-2和GB/T 311.1—1997标准推荐的方法进行海拔校正,并与北京的试验基地得到的试验结果进行比较,结果表明以上3种标准推荐的海拔校正方法已不适用于海拔4.3 km的长空气间隙操作冲击放电。最后,按照＂海拔每升高100m,绝缘的电气强度降低相同百分比＂的原则,采用插值法计算得到了海拔4300m及以下地区的塔头间隙操作冲击放电电压曲线,并结合±1000kV直流输电线路过电压的研究结果,计算了不同海拔下±1000kV直流输电线路塔头操作过电压需要的最小空气间隙距离。在1.7pu操作过电压下,对于海拔1000m及以下地区,±1000kV直流塔头的空气间隙距离建议为8.6m;当海拔为3500m时,建议为9.8m。
±1000 kV직류재중국시일개신적전압등급,위보증설계적경제성화가고성,수대불동해발지구공기간극거리적선택진행시험연구。재북경적특고압직류시험기지화해발4 300 m적서장고해발시험기지채용상동결구적±1 000 kV진형척촌모의탑두공기간극진행료충격방전시험,획득료상응적조작충격화뇌전충격방전특성곡선。통과대서장기지득도적조작충격방전전압채용GB/T 16927.1—1997、IEC 60071-2화GB/T 311.1—1997표준추천적방법진행해발교정,병여북경적시험기지득도적시험결과진행비교,결과표명이상3충표준추천적해발교정방법이불괄용우해발4.3 km적장공기간극조작충격방전。최후,안조＂해발매승고100m,절연적전기강도강저상동백분비＂적원칙,채용삽치법계산득도료해발4300m급이하지구적탑두간극조작충격방전전압곡선,병결합±1000kV직류수전선로과전압적연구결과,계산료불동해발하±1000kV직류수전선로탑두조작과전압수요적최소공기간극거리。재1.7pu조작과전압하,대우해발1000m급이하지구,±1000kV직류탑두적공기간극거리건의위8.6m;당해발위3500m시,건의위9.8m。
The ±1000kV DC transmission system is at a new voltage level in China.In order to guarantee the design reliability and rationality,the air clearance choice is very important and need to be researched.The same configuration and real size simulation tower head of ±1000kV DC lines were used to carry out impulse voltage test at the UHVDC test base in Beijing and the Tibet high altitude test base located at 4 300 m above sea level.The test curve of flashover characteristics of switching impulse and lightning impulse were acquired.It is found that the altitude correction methods recommended by standards of GB/T 16927.1-1997,IEC 60071-2：1996 and GB/T 311.1-1997 are no longer suit for the long air gap discharge voltage at an altitude of 4 300 m by using the methods recommended by the three standards on the switching impulse test results acquired in Tibet and compared with the test results got in Beijing.Finally,the insertion method based on the principle of ＂when the altitude rises with 100 m,the related insulation level would drop with the equal percentage＂ was used to calculate the switching impulse discharge voltage curves below altitude of 4 300 m,and by considering the over-voltage research results for ±1000kV DC transmission lines,the minimum gap distances for ±1000kV DC tower head under switching over-voltage at different altitudes were calculated.While the switching over voltage is 1.7pu,the minimum air clearance on ±1000kV DC transmission line tower is suggested to be 8.6m respectively at the attitude below 1000m.At the attitude of 3500m,it＇s suggested that the minimum air clearance is 9.8 m.